SEX

I should have preferred phrasing so indelicate a matter more delicately, as with, "making love at this very moment" or, to employ an au courant White House euphemism, "not having an inappropriate relationship at this very moment."

But "having sex" is how sometimes-indelicate Kathleen Turner puts it, as narrator of what will no doubt be the most watched educational TV documentary series of the year: The Science of Sex, at 9 p.m. tonight through Thursday on The Learning Channel.

It has long been my belief that, in explaining all forms of human behavior, we'd do well to junk psychology, sociology and all the other mumbo-jumbo sciences and just stick with zoology.

For example, with his book The Naked Ape, zoologist Desmond Morris explained the behavior of virtually all the people living in New York City _ excepting, perhaps, Woody Allen and the late Truman Capote.

Like The Naked Ape, The Science of Sex employs the same scientific, dispassionate method used in such public television documentary shows as "Newts of the Kalahari" or "See the Hyena Eat the Baby Zebra."

The visuals in the Science of Sex are far more agreeable than zebra entrails _ though the series does not, alas, include any footage of Turner from her profoundly scientific film Body Heat.

There are a few scientific talking heads on view (though mercifully not wearing white lab coats), but otherwise the background visuals on the screen are almost entirely film and video clips of men and women in swimsuits at poolside or pitching woo in discos.

In all other respects, the series grapples with its subject as scientifically as Carl Sagan used to grapple with the cosmos.

It's full of fascinating facts, for example: Women wear more makeup and dress more sexily while ovulating. Chimpanzes often kiss like humans.

The series' essential conclusion is one voiced incongruously by Capote some years ago: Sex is all that life is about.

Reproducing ourselves and passing our genes on to the next generation, say Turner and the scientists, is our only reason for milling about on this planet.

True, we don't abruptly die immediately after spawning, like so many salmon and squid. We employ face lifts, hormone treatments and the like in the hope of keeping the spawning thing going.

But gene-passing is all we really have in mind, according to this series, and, contrary as it might be to feminist principles, political correctness and sexual harassment codes, it's what drives and shapes our mating habits entirely. We may ask about zodiac signs, but what we're after is gene transfer.

These mating habits are the result of a couple of million years of "sexual evolution," and have been little affected by feminist tracts or the advent of women in the workplace.

In terms of sexual attraction, man is still the hunter/gatherer and woman remains the mother/nurturer, and they conduct themselves sexually accordingly, says the series.

Males may enjoy sex for its own sake and have several sex partners in life (on the average, eight, to a woman's one or two), but (if only subconsciously) men select a mate on the basis of whether she looks healthy and sturdy enough to bear offspring (a judgment males can make just looking at a woman from behind, according to the series).

Women are in it for the long haul, and (in terms of their sex drive) look for a mate who can get them through pregnancy and child-rearing in comfy fashion.

Consequently, women are most sexually attracted to men who exhibit maturity, wealth, status and intelligence, while men are attracted most to women whose physical allure is health and athletic form _ the ideal form being one in which the female waist is never more or less than two-thirds the circumference of the hips.

One fascinating finding of the series is that symmetry in bodies and faces is a big component of sexual attraction. According to Turner, symmetrical men may have as much as 20 times the number of sex partners as markedly asymmetrical men.

And if that statistic sounds a little goofy, consider the two pictorial examples the series' producers seized upon as illustration of this symmetrical attraction (and remember, the series was filmed last year).

One, predictably enough, was Paul Newman. The other was President Bill Clinton.